Final answer:
To investigate suspicion of sick sinus syndrome, prolonged ECG monitoring such as Holter monitoring or event monitoring is recommended, complemented by an echocardiogram and, if necessary, exercise stress tests.
Step-by-step explanation:
The most appropriate diagnostic method to investigate the suspicion of sick sinus syndrome in a 31-year-old woman experiencing lightheadedness, syncope, and occasional palpitations with a finding of sinus bradycardia on a resting ECG would be a combination of tools. While an ECG provides valuable information, given its limitations, additional testing such as prolonged ECG monitoring (e.g., Holter monitoring or event monitoring) is often recommended to capture and assess episodes occurring outside a clinical setting. This can be crucial as tachycardia and arrhythmias may not always be present during a standard ECG recording. Other diagnostic methods could include an echocardiogram to evaluate the effectiveness of heart pumping and structure, or exercise stress tests to study heart rhythms under physical exertion.
Diagnostic tools like Holter monitoring and echocardiograms are also valuable in assessing symptoms related to bradycardia, which, if severe, could result in insufficient oxygenated blood being supplied to the tissues. Since this patient's bradycardia is symptomatic, these investigations can help determine the necessity for potential treatments, which might include lifestyle changes, medication adjustments, or the installation of a pacemaker.